TECHNICAL FIELD
[0001] The present invention relates to a method for producing a carbon material and a carbon
material, particularly relates to a method using a cellulosic material and/or a regenerated
cellulosic material and enabling a carbon material, which retains the shape of the
cellulosic material and/or the regenerated cellulosic material, to be produced in
high yield, and a carbon material obtained through the production method, which retains
the shape of the raw material.
BACKGROUND ART
[0002] Carbon materials derived from cellulosic materials and/or regenerated cellulosic
materials as the raw materials thereof are used in a variety of fields. Currently,
such carbon materials are used in the form of a fiber, particle, or mass in many cases,
while there are very few application examples of carbon materials in a thin planar
form such as film or membrane. Examples of such a planar-form carbon material include
conductive carbon paper or cloth, which is a carbon fiber product used as a material
for a gas diffusion layer in an electrode of a fuel cell and is quite expensive.
[0003] It is appreciated that heating a cellulosic material at high temperature in an inert
gas results in dehydration and depolymerization of the cellulosic material through
pyrolysis, induces complex degradation reactions, which include generation of low-molecular-weight
materials such as levoglucosan, and the like; as well as it produces CO, CO
2, H
2O, and other volatile gases, and finally leaves a black material composed mainly of
carbon (Non-patent Documents 1 and 2).
[0004] Due to such features of pyrolysis, it is quite difficult for a cellulosic material
having a form of, for example, film to retain the shape thereof and the obtained carbon
material is very fragile.
[0005] Recently, a technology which takes advantage of the properties of cellulosic materials
has been reported, in which network-type and sheet-type carbon materials, which have
large specific surface areas and novel configurations and varied graphitization rates,
can be obtained in high yield from a gel-like bacterial cellulose produced by a bacteria
(Patent Document 1). Moreover, recently, the inventors have reported that a carbon
material which retains the shape of a cellulosic material can be provided by treating
the cellulosic material with a halogen or a halide prior to heat treatment (Patent
Document 2).
[0006] Also in the background art is Patent Document 3, which concerns the provision of
a gas diffusion layer for a fuel cell, the diffusion layer for the fuel cell being
made of a carbon material prepared by treating a cellulosic material with a halogen
or halide prior to heat treatment. There is also Patent Document 4, which is concerned
with the production of porous carbon fibers, the production process including the
step of adding acid to a gelled starch solution. There is also Patent Document 5,
which is towards the production of a carbonaceous material by carbonizing and sulfonating
a polymer.
RELATED ART DOCUMENTS
PATENT DOCUMENTS
[0007]
Patent Document 1: Japanese Unexamined Patent Application Publication No. 2007-55865
Patent Document 2: Japanese Unexamined Patent Application Publication No. 2009-292676
Patent Document 3: Publication No JP 2011 113768
Patent Document 4: Publication No US 2010/081351
Patent Document 5: Publication No EP 2 159 193
NON-PATENT DOCUMENTS
[0008]
Non-patent Document 1: Pielichowski, K., and Njuguna, J. Thermal Degradation of Polymeric Materials, Rapra,
Shawbury, UK, 2005.
Non-patent Document 2: Bridgwater, A.V., Hofbauer, H., Van Loo, S. Thermal Biomass Conversion, CPL Press,
London, UK, 2009.
SUMMARY OF THE INVENTION
PROBLEMS TO BE SOLVED BY THE INVENTION
[0009] The above-described Patent Document 1 has reported that a carbon material can be
obtained excellently from a bacterial cellulosic material. However, since the bacterial
cellulosic material is a gelatinous material, problems associated with a bacterial
cellulosic material arose, in which the bacterial cellulose should be dried at a drying
step while the network configuration thereof was retained; furthermore, the shrinkage
rate of the bacterial cellulose should be controlled during the drying step to be
within a predefined range; and the like. Moreover, the production method described
in Patent Document 2 uses a halogen gas and therefore has a feature that the halogen
molecules are adsorbed to cellulose in the gas phase and requires some attention to
handling the halogen, which proves that the production method has room for improvement.
[0010] Thus, the purpose of the present invention is to provide a method for producing a
carbon material, the method utilizing a cellulosic material and/or a regenerated cellulosic
material to produce a carbon material in high yield which retains the shape of the
cellulosic material and/or the regenerated cellulosic material.
MEANS FOR SOLVING THE PROBLEMS
[0011] The inventors studied intensively and eventually found that the above-described problems
can be resolved by using a sulfonic acid as a catalyst for carbonization, which is
relatively easy to handle, and thereby completed the present invention.
[0012] That is, a method for producing a carbon material of the present invention comprises
the steps of: allowing a cellulosic material and/or a regenerated cellulosic material
to adsorb a sulfonic acid; and heating the cellulosic material and/or the regenerated
cellulosic material which has adsorbed the sulfonic acid at a temperature of 600-2800°C,
and preferably of 600-1000°C, in an inert gas atmosphere, wherein the step of adsorbing
the sulfonic acid is performed by immersing a cellulosic material in an aqueous solution
of the sulfonic acid; and the concentration of the sulfonic acid in the aqueous solution
is 0.1-2.0 mol/L.
[0013] Moreover, the method for producing a carbon material of the present invention may
further comprise the steps of: cooling the heat-treated cellulosic material and/or
regenerated cellulosic material to room temperature and subsequently reheating the
heat-treated cellulosic material and/or regenerated cellulosic material at a temperature
of
1800-3000°C in an inert gas atmosphere.
[0014] In the methods for producing a carbon material of the present invention, the step
of adsorbing the sulfonic acid is carried out by immersing the cellulosic material
and/or the regenerated cellulosic material in an aqueous solution of the sulfonic
acid, preferably at room temperature.
[0015] In the methods for producing a carbon material of the present invention, the concentration
of the sulfonic acid in the aqueous solution is 0.1-2.0 mol/L.
[0016] Moreover, in the methods for producing a carbon material of the present invention,
the sulfonic acid may be either an aliphatic or aromatic sulfonic acid. Specifically,
any one of water-soluble sulfonic acids and the like such as methanesulfonic acid,
p-toluenesulfonic acid, naphthalenesulfonic acid, benzenesulfonic acid and camphorsulfonic
acid is preferably used alone.
[0017] Moreover, in the methods for producing a carbon material of the present invention,
the cellulosic material and/or the regenerated cellulosic material is preferably in
a form selected from the group consisting of spun yarn, monofilament, paper, film,
sheet, woven fabric and knitted fabric.
[0018] A carbon material of the present invention is obtained through either of the above-described
methods for producing a carbon material and characterized in that the form of a cellulosic
material and/or a regenerated cellulosic material used as a raw material is retained.
EFFECTS OF THE INVENTION
[0019] According to the present invention, in a cellulosic material which has adsorbed a
sulfonic acid, water (H
2O) is removed from cellulose molecules through the dehydrating function of the sulfonic
acid as temperature increases, and thus pyrolysis reaction is hardly induced and many
carbons in the cellulose molecules are left in the form of a carbonized material,
which therefore enables carbonization with high carbonization yield and shape-retention
capability to be achieved. Thus, carbonization of a cellulosic material with retaining
the shape thereof in such a manner also enables a conductive carbon film to be produced
in high carbonization yield from, for example, traditional Japanese paper.
MODE FOR CARRYING OUT THE INVENTION
[0020] Next, a method for producing a carbon material of the present invention will be described
below.
[0021] The method for producing a carbon material of the present invention is characterized
by comprising the steps of: allowing a cellulosic material and/or a regenerated cellulosic
material to adsorb a sulfonic acid; and heating the cellulosic material and/or the
regenerated cellulosic material which has adsorbed the sulfonic acid at a temperature
of 600-2800°C, and preferably of 600-1000°C, in an inert gas atmosphere, wherein the
step of adsorbing the sulfonic acid is performed by immersing a cellulosic material
in an aqueous solution of the sulfonic acid; and the concentration of the sulfonic
acid in the aqueous solution is 0.1-2.0 mol/L.
[0022] In the step of allowing a cellulosic material and/or a regenerated cellulosic material
to adsorb a sulfonic acid, the method is by immersion in an aqueous solution of a
sulfonic acid. Other examples of adsorbing sulfonic acid include a method in which
an aqueous solution of a sulfonic acid is sprinkled over a cellulosic material; a
method in which a cellulosic material is brought into contact with the vapor of a
vaporized sulfonic acid; a method in which a mixture of fibers of a cellulosic material
and/or a regenerated cellulosic material in an aqueous solution of a sulfonic acid
is subjected to paper-making; and the like.
[0023] The method disclosed herein requires immersing of a cellulosic material in an aqueous
solution of a sulfonic acid. The temperature at the time of immersion in an aqueous
solution of a sulfonic acid is not particularly limited, but room temperature is preferred.
The immersion time is preferably from 5 to 120 minutes, and more preferably from 5
to 30 minutes. The immersion allows the cellulosic material to adsorb, for example,
1-150% by mass of, and preferably 5-60% by mass of, a sulfonic acid. The cellulosic
material is preferably retrieved and dried after the immersion. Any method may be
acceptable as a drying method, including, for example, leaving the cellulosic material
at room temperature, placing the cellulosic material in a drying machine, and the
like. Drying may be continued until excess water is evaporated after retrieval of
the cellulosic material from the aqueous solution of a sulfonic acid and the sample
weight does not change any more. For example, in cases where drying is carried out
by leaving the cellulosic material at room temperature, the drying time may be a half
day or more. After almost no further mass change due to drying is observed, the cellulosic
material is subjected to the heating treatment step.
[0024] In the method for producing a carbon material of the present invention, cellulosic
materials and/or regenerated cellulosic materials used as raw materials refer to materials
mainly composed of cellulose derivatives. Cellulose and cellulose derivatives include
cellulose and cellulose derivatives of any origin, such as chemical compounds, plant-derived
cellulose, regenerated cellulose, cellulose produced by bacterium, and the like. Examples
thereof include plant cellulosic materials produced by higher plants including so-called
trees, and regenerated cellulosic materials composed of long fibers, which are produced
via dissolution of short cellulose fibers, which are collected from cotton and pulp,
by a chemical treatment. Cellulosic materials and/or regenerated cellulosic materials
are cellulosic materials in a variety of forms ranging from one dimensional to three
dimensional forms, including fibrous materials, film-shaped materials, or materials
in three dimensional configurations. The present invention has enabled destruction
of the shapes of even the materials in such various forms and reduction in carbon
yield during carbonization at high temperature to be prevented. Examples of preferred
cellulosic materials to obtain such effects include spun yarns, monofilaments, paper,
films, sheets, woven fabrics, knitted fabrics, absorbent cotton balls, and the like.
[0025] A variety of aliphatic and aromatic compounds having a sulfo group(s) can be used
as sulfonic acids. The cellulose molecule, which composes cellulosic materials and/or
regenerated cellulosic materials, is represented by a chemical formula: (C
6(H
2O)
5)
n, which is also considered to be a molecule composed of carbon and water. In the method
of the present invention, a sulfonic acid removes only water (H
2O) from cellulose molecules through the dehydrating function thereof during the heat
treatment of cellulosic materials and, thus, generation of a hydrocarbon gas, which
is associated with typical pyrolysis processes, does not occur and carbon components
in cellulose molecules are hardly lost, which is therefore considered to prevent reduction
of the finally remaining amount of carbon materials. A sulfonic acid which can be
used in the present invention may be any of organic compounds as long as a sulfo (-SO
3H) group(s) is/are attached to the carbon skeleton in each of the organic compounds,
and is preferred to be a low-molecular-weight compound that is handled easily. A single
or plural number of sulfo groups may be attached thereto. Specific examples of sulfonic
acids which can be used include, for example, compounds represented by R-SO
3H (wherein, R represents a linear or branched alkyl group having 1-20 carbon atoms,
a cycloalkyl group having 3-20 carbon atoms, or an aryl group having 6-20 carbon atoms,
each of which alkyl, cycloalkyl and aryl groups may be optionally substituted by a
alkyl group(s), a hydroxyl group(s), and/or a halogen atom(s)). Specific compound
examples of sulfonic acids include, for example, methanesulfonic acid, ethanesulfonic
acid, propanesulfonic acid, 1-hexanesulfonic acid, vinylsulfonic acid, cyclohexanesulfonic
acid, p-toluenesulfonic acid, p-phenolsulfonic acid, naphthalenesulfonic acid, benzenesulfonic
acid, camphorsulfonic acid, and the like. Preferably, the sulfonic acid is one or
more selected from the group consisting of methanesulfonic acid, p-toluenesulfonic
acid, naphthalenesulfonic acid, benzenesulfonic acid and camphorsulfonic acid. A sulfonic
acid may be used alone, or two or more sulfonic acids may be used in combination.
[0026] The method disclosed herein requires that an aqueous solution of a sulfonic acid
is used, where the concentration is 0.1-2.0 mol/L, preferably 0.5-1.0 mol/L.
[0027] Next, at the heat treatment step (carbonization step), the cellulosic material and/or
the regenerated cellulosic material, which has undergone the above-described adsorption
step with a sulfonic acid, is carbonized at a heating temperature of 600°C-2800°C,
and preferably of 600°C-1000°C, in an inert gas atmosphere. This allows a carbon material
to be obtained, in which the shape thereof is retained as it was. When this heating
temperature is less than 600°C, the carbon content in a carbonized material is not
more than 80% by mass, which means insufficient carbonization. On the other hand,
when the heating temperature is even more than 2800°C, the carbonization state is
hardly changed any further.
[0028] Specifically, for example, the cellulosic material and/or the regenerated cellulosic
material, which has undergone the above-described adsorption step with a sulfonic
acid, is first heated, with the shape thereof being retained, by using an electric
furnace at a temperature in the above-described range in a nitrogen or argon gas atmosphere.
The heating time in this step depends on the heating temperature and is preferably
0.5-1 hour. Moreover, the temperature rising rate from room temperature to a predefined
heating temperature is preferably 3-8°C/min. A high temperature furnace such as a
tubular furnace and an electric furnace can be used in an inert gas atmosphere at
the heat treatment step and in this case desulfurization of a sulfur-based gas, which
is generated from a sulfonic acid in a small quantity, is preferably carried out with
an exhaust pipe for the inert gas, which is packed with adsorptive materials such
as activated carbon.
[0029] Carbon materials can be obtained by the above-described method for producing a carbon
material of the present invention, with the shapes of cellulosic materials and/or
regenerated cellulosic materials used as raw materials being retained. Assuming that
all carbons contained in cellulose are left in the form of a carbonized material,
the carbonization yield would be theoretically 44.4% by mass. According to the present
invention, a carbon material having a high carbonization yield of preferably not less
than 30% by mass, and in some cases not less than 40% by mass, can be produced.
[0030] The method disclosed herein may further comprise the step of reheating the heat-treated
sample at a temperature of 1800-3000°C in an inert gas atmosphere. At the heat treatment
step, the cellulosic material and/or the regenerated cellulosic material, which has
undergone the absorption step with a sulfonic acid, is first carbonized in a similar
manner to that described above at a heating temperature of not less than 600°C and
not more than 2800°C in an inert gas atmosphere. The heating time in this step depends
on the heating temperature and is preferably 0.5-1 hour. This allows a carbon material
to be obtained, in which the shape of the cellulosic material is retained as it was.
[0031] Then, at the reheating step (partial graphitization step), preferably after returning
the temperature of the carbon material, which has heat-treated at the above-described
step, to room temperature, reheating is carried out at a temperature of 1800°C-3000°C,
and preferably of 1800°C-2800°C, in an inert gas atmosphere. This allows a carbon
material to be obtained, which retains the original shape of the cellulosic material
and is partially graphitized. When this reheating temperature is less than 1800°C,
graphitization (crystallization) hardly proceeds. On the other hand, when the reheating
temperature is even more than 3000°C, the extent of graphitization is hardly changed
any further.
[0032] Specifically, for example, the carbon material, which has been obtained at the carbonization
step, is heated in a similar manner to that in the carbonization step, with the shape
thereof being retained, by using an electric furnace at a temperature in the above-described
range in an argon gas atmosphere. The heating time depends on the heating temperature
and is preferably 0.5-1 hour.
[0033] Additionally, in another production method of the present invention, a carbon material,
which has been obtained through carbonization at a temperature of 600°C-1000°C, may
be further heated for partial graphitization at a temperature of 1800°C-3000°C after
cooling down the carbon material to room temperature once, or a carbon material, which
has been obtained through carbonization at a temperature of 600°C-1000°C, may be immediately
reheated for graphitization to a temperature of 1800°C-3000°C in a continuous manner,
which can provide a similar effect on graphitization.
[0034] A carbon material obtained through the first carbonization process is a material
having a conductivity of a few Siemens per cm, which almost retains the shape thereof,
although some shrinkage in size is observed. Heating this carbon material at a temperature
of 1800°C-3000°C in the partial graphitization process allows graphitization to proceed
in the material, which results in improvement of the conductivity and the conductivity
increases to not less than tens of Siemens per cm.
EXAMPLES
[Example 1]
[0035] A sheet of sample sisal paper produced by a traditional Japanese paper making method
(60 × 80 mm, 0.5 mm of thickness) was immersed in a 0.1 mol/L aqueous solution of
p-toluenesulfonic acid for 10 minutes at room temperature. Then, the sisal paper produced
by a traditional Japanese paper making method was retrieved from the aqueous solution
and dried for 12 hours at room temperature. The content of the adsorbed sulfonic acid
was 9% by mass. This sample was sandwiched between two carbon plates and heated using
an electric furnace for 60 minutes at 800°C in an argon gas atmosphere to carry out
carbonization. At this step, an exhaust pipe for argon gas contained a small amount
of activated charcoal for desulfurization. After carbonization, the electric furnace
was cooled down to room temperature and the carbonized sample (carbonized paper) was
retrieved. The carbonization yield thereof was identified and the carbonization yield
was 32% by mass.
[Example 2]
[0036] Carbonized paper was produced in a similar manner to that in Example 1, except that
1.0 mol/L of methanesulfonic acid was used instead of p-toluenesulfonic acid. The
content of the absorbed methanesulfonic acid was 60% by mass. The carbonization yield
of the obtained carbonized paper was 38% by mass.
[Comparative Example 1]
[0037] A sheet of sisal paper produced by a traditional Japanese paper making method as
used in Example 1 was not immersed in p-toluenesulfonic acid and immediately heated
using an electric furnace for 60 minutes at 800°C in an argon gas atmosphere to carry
out carbonization. After carbonization, the electric furnace was cooled down to room
temperature and the carbonized sample was retrieved. The carbonization yield thereof
was identified and the carbonization yield was 17% by mass.
[Example 3]
[0038] A sheet of sample gampi (
Diplomorpha sikokiana) paper produced by a traditional Japanese paper making method (80 × 100 mm, 0.3 mm
of thickness) was immersed in a 0.1 mol/L aqueous solution of p-toluenesulfonic acid
for 20 minutes at room temperature. Then, the gampi paper produced by a traditional
Japanese paper making method was retrieved from the aqueous solution and dried for
36 hours at room temperature. The content of the adsorbed sulfonic acid was 6% by
mass. This sample was heated by a method totally identical to that in Example 1 to
produce carbonized paper. The carbonization yield thereof was identified and the carbonization
yield was 32% by mass.
[Example 4]
[0039] Carbonization was carried out in a similar manner to that in Example 3, except that
1.0 mol/L of methanesulfonic acid was used instead of p-toluenesulfonic acid. The
content of the absorbed methanesulfonic acid was 61% by mass. The carbonization yield
of the obtained carbonized paper was 35% by mass.
[Comparative Example 2]
[0040] A sheet of gampi paper produced by a traditional Japanese paper making method as
used in Example 3 was not immersed in p-toluenesulfonic acid and immediately heated
using an electric furnace for 60 minutes at 800°C in an argon gas atmosphere to carry
out carbonization. After carbonization, the electric furnace was cooled down to room
temperature and the carbonized sample was retrieved. The carbonization yield thereof
was identified and the carbonization yield was 18% by mass.
[Example 5]
[0041] A sheet of sample regenerated cellulose paper (60 × 67 mm, 0.53 mm of thickness)
was immersed in a 0.1 mol/L aqueous solution of p-toluenesulfonic acid for 10 minutes
at room temperature. Then, the sample was retrieved from the aqueous solution and
dried for 36 hours at room temperature. The content of the adsorbed sulfonic acid
was 14% by mass. This sample was heated by a method totally identical to that in Example
1 to produce carbonized paper. The carbonization yield thereof was identified and
the carbonization yield was 33% by mass.
[Example 6]
[0042] A sheet of sample filter paper (80 × 100 mm, 0.34 mm of thickness) was immersed in
a 1.0 mol/L aqueous solution of methanesulfonic acid for 20 minutes at room temperature.
Then, the sample was retrieved from the aqueous solution and dried for 36 hours at
room temperature. The content of the adsorbed sulfonic acid was 38% by mass. This
sample was heated by a method totally identical to that in Example 1 to produce carbonized
paper. The carbonization yield thereof was identified and the carbonization yield
was 35% by mass.
[Example 7]
[0043] A sample cotton thread (spun yarn, 1 mm of diameter) was immersed in a 2.0 mol/L
aqueous solution of methanesulfonic acid for 120 minutes at room temperature. Then,
the sample was retrieved from the aqueous solution and dried for 12 hours at room
temperature. The content of the adsorbed sulfonic acid was 43% by mass. This sample
was heated by a method totally identical to that in Example 1 to carry out carbonization
to produce a carbon fiber. The carbonization yield thereof was identified and the
carbonization yield was 38% by mass.
[Example 8]
[0044] A sample, a commercial absorbent cotton ball, was immersed in a 0.1 mol/L aqueous
solution of p-toluenesulfonic acid for 10 minutes at room temperature. Then, the sample
was retrieved from the aqueous solution and dried for 36 hours at room temperature.
The content of the adsorbed sulfonic acid was 46% by mass. This sample was heated
by a method totally identical to that in Example 1 to produce a carbonized absorbent
cotton ball. The carbonization yield thereof was identified and the carbonization
yield was 40% by mass.
INDUSTRIAL APPLICABILITY
[0045] Carbon materials obtained through the production methods of the present invention
are quite useful for carbon films, carbon fibers, materials for various electronic
devices such as a nano-conductive material, electrode materials for various cells,
various gas storage materials, various gas storage and adsorption materials, heat
conductive and emitting materials, catalyst carriers, filter media, electron emission
materials, and the like.
1. A method for producing a carbon material, the method comprising the steps of:
allowing a cellulosic material and/or a regenerated cellulosic material to adsorb
a sulfonic acid; and heating the cellulosic material and/or the regenerated cellulosic
material which has adsorbed the sulfonic acid at a temperature of 600-2800°C in an
inert gas atmosphere; wherein
the step of adsorbing the sulfonic acid is performed by immersing a cellulosic material
in an aqueous solution of the sulfonic acid; and
the concentration of the sulfonic acid in the aqueous solution is 0.1-2.0 mol/L.
2. The method for producing a carbon material according to claim 1, wherein the method
further comprises reheating the heat-treated cellulosic material at a temperature
of 1800-3000°C in an inert gas atmosphere.
3. The method for producing a carbon material according to claim 1, wherein the sulfonic
acid is one or more selected from the group consisting of methanesulfonic acid, p-toluenesulfonic
acid, naphthalenesulfonic acid, benzenesulfonic acid and camphorsulfonic acid.
4. The method for producing a carbon material according to claim 1, wherein the cellulosic
material and/or the regenerated cellulosic material is selected from the group consisting
of spun yarn, monofilament, paper, film, sheet, woven fabric and knitted fabric.
5. The method for producing a carbon material according to claim 1, wherein the heating
time of the heating step is 0.5-1 hour.
6. The method for producing a carbon material according to claim 1, wherein the temperature
increase rate of the heating step is 3-8°C/min.
7. The method for producing a carbon material according to claim 1, wherein the carbon
material obtained after the step of heating retains the form of the cellulosic material
and/or the regenerated cellulosic material.
8. The method for producing a carbon material according to claim 1, wherein the cellulosic
material and/or the regenerated cellulosic material is selected from the group consisting
of spun yarn, monofilament, paper, film, sheet, woven fabric and knitted fabric; and
wherein the carbon material obtained after the step of heating retains the form of
the cellulosic material and/or the regenerated cellulosic material.
1. Verfahren zur Herstellung eines Kohlenstoffmaterials, wobei das Verfahren die folgenden
Schritte umfasst:
Ermöglichen, dass ein Cellulosematerial und/oder regeneriertes Cellulosematerial eine
Sulfonsäure adsorbieren kann; und Erhitzen des Cellulosematerials und/oder des regenerierten
Cellulosematerials, das die Sulfonsäure adsorbiert hat, bei einer Temperatur von 600-2800°C
in einer Inertgasatmosphäre;
wobei
der Schritt des Adsorbierens der Sulfonsäure durch Immersion eines Cellulosematerials
in einer wässrigen Lösung der Sulfonsäure durchgeführt wird; und
die Konzentration der Sulfonsäure in der wässrigen Lösung 0,1 - 2,0 mol/l beträgt.
2. Das Verfahren zur Herstellung eines Kohlenstoffmaterials entsprechend Anspruch 1,
wobei das Verfahren zudem das erneute Erhitzen des wärmebehandelten Cellulosematerials
bei einer Temperatur von 1800-3000°C in einer Inertgasatmosphäre umfasst.
3. Das Verfahren zur Herstellung eines Kohlenstoffmaterials entsprechend Anspruch 1,
wobei es sich bei der Sulfonsäure um eine oder mehrere handelt, die aus der Gruppe
bestehend aus Methansulfonsäure, p-Toluolsulfonsäure, Naphthalinsulfonsäure, Benzensulfonsäure
und Camphersulfonsäure ausgewählt wird/werden.
4. Das Verfahren zur Herstellung eines Kohlenstoffmaterials entsprechend Anspruch 1,
wobei das Cellulosematerial und/der regenerierte Cellulosematerial aus der Gruppe
bestehend aus Spinnfasergarn, Monofil, Papier, Film, Folie, Gewebe und Gestrick ausgewählt
wird.
5. Das Verfahren zur Herstellung eines Kohlenstoffmaterials entsprechend Anspruch 1,
wobei die Erwärmungszeit des Schritts des Erhitzens 0,5 - 1 Stunde beträgt.
6. Das Verfahren zur Herstellung eines Kohlenstoffmaterials entsprechend Anspruch 1,
wobei die Temperaturanstiegsrate des Schritts des Erhitzens 3-8°C beträgt.
7. Das Verfahren zur Herstellung eines Kohlenstoffmaterials entsprechend Anspruch 1,
wobei das nach dem Schritt des Erhitzens erhaltene Kohlenstoffmaterial die Form des
Cellulosematerials und/oder des regenerierten Cellulosematerials beibehält.
8. Das Verfahren zur Herstellung eines Kohlenstoffmaterials entsprechend Anspruch 1,
wobei das Cellulosematerial und/oder das regenerierte Cellulosematerial aus der Gruppe
bestehend aus Spinnfasergarn, Monofil, Papier, Film, Folie, Gewebe und Gestrick ausgewählt
wird;
und
wobei das nach dem Schritt des Erhitzens erhaltene Kohlenstoffmaterial die Form des
Cellulosematerials und/oder des regenerierten Cellulosematerials beibehält.
1. Procédé de production de matériau carboné, le procédé comprenant les étapes consistant
à :
laisser un matériau cellulosique et/ou un matériau cellulosique régénéré adsorber
un acide sulfonique ; et chauffer le matériau cellulosique et/ou le matériau cellulosique
régénéré qui a adsorbé l'acide sulfonique à une température de 600 à 2800 °C dans
une atmosphère inerte ;
dans lequel
l'étape d'adsorption de l'acide sulfonique est réalisée en immergeant un matériau
cellulosique dans une solution aqueuse de l'acide sulfonique ; et
la concentration de l'acide sulfonique dans la solution aqueuse est de 0,1 à 2,0 mol/l.
2. Procédé de production de matériau carboné selon la revendication 1, le procédé comprenant
en outre le réchauffement du matériau cellulosique prétraité à une température de
1800 à 3000 °C dans une atmosphère inerte.
3. Procédé de production d'un matériau carboné selon la revendication 1, dans lequel
l'acide sulfonique est un ou plusieurs composés sélectionnés dans le groupe constitué
d'acide méthane sulfonique, d'acide p-toluène sulfonique, d'acide naphtalène sulfonique,
d'acide benzène sulfonique et d'acide camphre sulfonique.
4. Procédé de production de matériau carboné selon la revendication 1, dans lequel le
matériau cellulosique et/ou le matériau cellulosique régénéré est sélectionné dans
le groupe constitué de fil filé, de mono filament, de papier, de film, de feuille,
de tissu tissé et de tissu tricoté.
5. Procédé de production d'un matériau carboné selon la revendication 1, dans lequel
le temps de chauffage de l'étape de chauffage est de 0,5 à 1 heure.
6. Procédé de production d'un matériau carboné selon la revendication 1, dans lequel
le taux d'augmentation de température de l'étape de chauffage est de 3 à 8 °C/min.
7. Procédé de production d'un matériau carboné selon la revendication 1, dans lequel
le matériau carboné obtenu après l'étape de chauffage garde la forme du matériau cellulosique
et/ou du matériau cellulosique régénéré.
8. Procédé de production d'un matériau carboné selon la revendication 1, dans lequel
le matériau cellulosique et/ou le matériau cellulosique régénéré est/sont sélectionné(s)
dans le groupe constitué de fil filé, de mono filament, de papier, de film, de feuille,
de tissu tissé et de tissu tricoté ;
et
où le matériau carboné obtenu après l'étape de chauffage garde la forme du matériau
cellulosique et/ou du matériau cellulosique régénéré.